"Rugged design provides continuous operation in workshops, barns, poultry houses, greenhouses, garages, anywhere air movement controls condensation and reduces stagnant air. 12in. fan delivers 1580 CFM @ 1625 RPM. U.S.A. Speed RPM 1,625, Air Delivery CFM 1,580, Depth in. 13 1/2, Speeds qty. 1, HP 1/16, Needs to be Hardwired Yes, Fan Diameter in. 12, Dimensions L x H in. 18 5/8 x 18 5/8 includes the flanges, Volts 115. Totally enclosed air over TEAO thermally protected motor Heavy-gauge galvanized steel fan frame reduces rust and corrosion Built-in shutter opens automatically when fan is turned on and closes when fan is turned off Spiral guard has a polyester powder-coat finish and meets OSHA requirements Built-in shutter with rigid blades for long-lasting, continuous operation Must be hardwired"